Embodiments are generally related to toggle switches. Embodiments are also related to toggle switch components, such as bushing and mounting nuts.
A toggle switch is a switch in which a projecting lever with a spring can be utilized to open or to close an electric circuit. Toggle switches of various types have long been utilized to control power in domestic, commercial, industrial, and military applications for operating various electrical devices and equipment.
Known toggle switches typically are manufactured with a housing that contains electrical contacts and is fitted with a manually operable handle to switch power to externally mounted terminals. In one common form of a toggle switch, the handle has a cam surface internal to the housing that actuates a metallic leaf spring which in turn makes or breaks electrical conductivity with the contacts. Common toggle switches are standardized in terms of their mounting configurations such that they can readily be installed in wall-mounted electrical boxes, for example, with only the use of two screws. Typically, screw terminals are positioned on the sides of the switch housing such that connection can be easily made to electrical wires of suitable size to deliver power to electrical devices or equipment.
Toggle switches typically provide a manually accessible member which has metastability in a first position and a second position. For example, these positions may represent xe2x80x9cONxe2x80x9d and xe2x80x9cOFFxe2x80x9d. Some situations provide a substantial penalty for accidental actuation. For example, during repair or installation, accidental actuation may result in electrocution or shock. Therefore, where a worker is not in the immediate vicinity of a switch and is in the process of installation, repair or maintenance, often a lock or flag is placed to alert others that the switch should not be reset or to prevent resetting without significant efforts.
FIG. 1 is a perspective view of a conventional toggle switch 28. In FIG. 1, a toggle lever assembly 30 generally includes a toggle lever 32 that projects from a bushing 34 that is secured to a cover 36. The cover 36 is connected to a case 38. A number of terminals 40 can project from the case 38 to make external electrical connections that are to be switched by the toggle switch 28. Note that FIGS. 1 and 2 are described and illustrated herein for general background and edification purposes only and do not represent limiting features of the present invention, nor a limitation of any embodiments thereof.
FIG. 2 is a sectional side view of the conventional toggle switch 28, taken along section lines 2xe2x80x942 of FIG. 1. In FIG. 2, the toggle lever 32 can be inserted in the bushing 34. A spherical section 46 of the toggle lever 32 generally rests an a spherical surface 48 of the bushing 34 and is held in place by a retaining ring 50 so that the toggle lever 32 pivots by sliding against the surface 48 and the retaining ring 50, which thus functions also as a bearing. The toggle lever 32, the bushing 34, the retaining ring 50, and the cover 36 when assembled comprise the toggle lever assembly 30.
In the alternative, the spherical section 46 may be pinned to the bushing 34 to support the toggle lever 32 and also provide support to rotate the toggle lever 32. The toggle lever assembly can be most readily assembled by connecting the bushing 34 to the cover 36. The toggle lever 32 can then be inserted into the bushing 34, and the retaining ring 50 (or a pin, if one is used) is placed to complete the assembly.
The toggle lever assembly 30 can be inserted into the case 38, where it is held in place by crimping the corners of the cover 36 to the case 38. A headed portion 52 may be rolled, glued, welded, swaged or otherwise shaped to secure the bushing 34 to the cover 36, which in turn is secured to the case 38 as described above.
A terminal 60 can be molded or otherwise inserted into the case 38 on one side and a terminal 62 is inserted correspondingly on the other side. The terminal 60 may include a shaped contact ball 64 that is inside the case 38 and a terminal pin 66 that is outside. Similarly, the terminal 62 includes a shaped contact ball 68 that is inside the case 38 and a terminal pin 70 that is outside.
A terminal 76, which is located between the terminals 60 and 62, has a terminal pin 78 that is outside the case 38. The terminal 76 is molded or otherwise inserted into the case 38 and is riveted, swaged, staked or the like to connect it to a blade 80. The blade 80 has a contact 82 that is placed opposite the shaped contact ball 64 and a contact 84 that is placed opposite the shaped contact ball 68. Such a switch generally establishes electrical contact between the terminal pins 66 and 78 by pressing the blade 80 to place the contact 82 against the shaped contact ball 64. Similarly, the electrical contact between the terminal pins 70 and 78 can be established by pressing the blade 80 to place the contact 84 against the shaped contact ball 68.
Each of these switching operations can be affected by rocking an actuator 86 in response to a force exerted by a plunger 88, which in turn is operated by an end 90 of the toggle lever 32. The spring action of the blade 80 provides a restoring force to open the switch by separating the contact 82 from the shaped contact ball 64 and the contact 84 from the shaped contact ball 68. It will be seen that the shape of the actuator 86 determines whether or not the action of the switch will be such as to maintain a selected position or to return from that position.
A coil spring 92 can be coaxial with and enclose the toggle lever 32 and may also be compressed by the spherical section 46 of the toggle lever 32 to force a tip 94 of the plunger 88 against the actuator 86. The fact that the coil spring 92 surrounds the toggle lever 32 allows the coil spring 92 to be larger in coiled diameter and thus sturdier than it would be if it were sized for insertion into the toggle lever 32.
Thus, conventional toggle switches, such as the example illustrated and described above with respect to FIGS. 1 and 2 utilize a threaded bushing and mounting nut to secure the device to a fixture or panel. One of the primary problems with such toggle switches, is that it is every easy to cross-thread the mounting nut during installation, thereby rendering the toggle switch useless.
The following summary of the invention is provided to facilitate an understanding of some of the innovative features unique to the present invention and is not intended to be a full description. A full appreciation of the various aspects of the invention can be gained by taking the entire specification, claims, drawings, and abstract as a whole.
It is, therefore, one aspect of the present invention to provide an improved toggle switch apparatus and method.
It is another aspect of the present invention to provide for an improved cover for a toggle switch.
It is yet a further aspect of the present invention to ensure proper alignment of a toggle switch and components thereof.
It is an additional aspect of the present invention to prevent cross threading due to misalignment of toggle switch components.
The aforementioned aspects of the invention and other objectives and advantages can now be achieved as described herein. A toggle switch cover apparatus and method are disclosed, which includes a mounting nut and a bushing for a toggle switch, such that the bushing comprises a threaded area and an uppermost unthreaded area. The uppermost unthreaded area comprises a maximum outside diameter that is less than a corresponding minimum minor diameter of threads of the mounting nut. The unthreaded portion or unthreaded area is generally located between the uppermost area of the bushing and the mounting nut, thereby promoting proper alignment of the toggle switch thereof and decreasing cross-threading issues. The toggle switch itself can include a toggle, wherein a portion of the toggle is surrounded by the mounting nut and the bushing. The mounting nut is positionable on the bushing in the uppermost unthreaded area thereof in a plane perpendicular to an axis of the bushing prior to a threading of the mounting nut onto the bushing. The bushing r comprises a plurality of threads for engaging corresponding mating threads of the mounting nut.